[EM] Symmetric ICT reformulation and exploration

[Michael Ossipoff]

I'd say that MDDTR is better, but I'd guess that Buckln might be more
likely to get enacted, because of its use-prededent, and because opponents
could use Mono-Add-Plump against MDDTR (and proponents might not have as
much media availabiliy to answer adequately).

But a proposal should include all of the best possibilities:

Approval
Score
Bucklin
MDDTR (re-named "Majority-Disqualification")

Then, the initiative-proposal-committee, and the public, via polls &
focus-groups, would choose among those methods, for the initiative.

I'd say that Approval's plain naturalness & obviousness, an its no-cost
implementation would make it the easiest & most easily enacted 1st reform
from Plurality.

Michael Ossipoff

On Sat, Nov 12, 2016 at 4:46 PM, Michael Ossipoff <email9648742 at gmail.com>
wrote:

> I forgot to add Mono-Add-Plump to the advantages of Buclin over MDDTR. So
> it should say:
>
> Bucklin:
>
> * Mono-Add-Plump
>
> * Use-Precedence
>
> * Easier protection of the CWs
>
> MDDTR:
>
> *CD
>
> *LNHa
>
> * Precinct-Summabilty
>
> -----------------------------------------
>
> If Bucklin's easier protection is in question, then the comparison is
> especially more favorable to MDDTR.
>
> Michael Ossipoff
>
>
>
> On Sat, Nov 12, 2016 at 4:32 PM, Michael Ossipoff <email9648742 at gmail.com>
> wrote:
>
>> Yes, that 2/3 majority rule would avoid having to say:
>>
>> "(If each candidate has someone rated over hir by a majority, then the
>> winner is the most top-rated candidate.)"
>>
>> Tantalizingly greater simplicity, regrettably not workable, as you said.
>>
>> ICT would avoid the Mono-Add-Plump criticism, but at the cost of
>> truncation-vulnerability.
>> I'd rather have the Mono-Add-Plump criticism and truncation-proofness.
>>
>> The ICT wording you described comes closer to the brevity of MDDTR, but
>> MDDTR doesn't need a separate "beat" definition at all. ...just the use of
>> the already-understood majority.
>>
>> I suggested the 3-slot version of MDDTR because I felt that it should be
>> used only as an Approval-version, with the Middle rating reserved for the
>> special chicken-dilemma situation.   ...because I felt that MDDTR, with its
>> complete vulnerability to burial (like every pairwise-count method),
>> wouldn't be good as a rank-method.
>>
>> But maybe that should be reconsidered. Why would it be worse to rank your
>> inbetween candidates in order of preference, than to rate them all together
>> at middle?
>>
>> The burial-vulnerability, the fact that "wv-like" didn't mean as much as
>> I'd believed it did,  was such a disappointment that it at first made me
>> not appreciate the fact that MDDTR still has truncation-resistance. Burial
>> vulnerability isn't a complete disaster:
>>
>> For one thing, to bury the CWs, you have to know who is the CWs. And if
>> you know it, then the defending wing knows it too, because the same
>> predictive information is available to everyone.
>>
>> If the CWs is more  with your wing, and it's the opposite wing that
>> dislikes the CWs, and is likely to bury, you can prevent successful burial
>> by equal-top-ranking the CWs. That was pointed out a long time ago, as
>> general pairwise-count defensive strategy.
>>
>> You could protect the CWs in that way in Bucklin too. (in case people
>> might rank past the CWs).
>>
>> Of course the difference is that, in Buclin you & the others in your wing
>> can also just avoid ranking past the CWse (expected or evident CWs).
>>
>> MDDTR, and pairwise-count methods in general, don't have that protection,
>> and you only have the defensive strategy of equal-top-ranking the CWse.
>>
>> So, as regards protection of the CWs, Bucklin is better than the
>> pairwise-count methods. MDDTR's tradeoff-advantage is its CD.  ...in return
>> for being able to protect the CWs only by equal-top-ranking.
>>
>> Conditional Bucklin's and Conditional Approval's FBC failure is of a
>> different kind than Condorcet's FBC failure, it seems to me. With
>> Conditional Bucklin, the effectiveness of my equal-top-ranking isn't
>> diminished by the FBC failure. The FBC failure merely gives me a trick that
>> I could use, with sufficient predictive information, to gain advantage. Not
>> a problem. But the problem is that the serious overcompromiser would still
>> have incentive to rank Hillary alone at top, over the overompromiser's
>> favorite. So I guess I reluctantly have to not advocate Conditional Bucklin
>> or Conditional Approval.
>>
>> ...meaning that evidently Bucklin can't have CD, and MDDTR's CD is an
>> advantage for MDDTR over Bucklin.  So it's MDDTR's CD vs Bucklin's easier
>> protection of the CWs.
>>
>> All that time I was calling wv burial-deterrent, because of the
>> 3-candidate example, where deterrence is achieved by merely not ranking the
>> would-be buriers' candidate, I never considered a 4-candidate example.
>>
>> It's easy to make a 4-candidate example where, in wv (& in MDDTR), that
>> defense won't work: If B is the CWs, and the A voters are going to bury by
>> insincerely ranking C over B, then just add D, between B and C.
>>
>> The halfway point between D & C is of course way C-ward from the median,
>> and so D will have a majority against C, if voters are
>> uniformly-distributed. (...and probably could, with suitable
>> distance-relations, even if the voter-distribution is Gaussian).
>>
>> So, when the A voters make B majority-beaten, by ranking C over B, C
>> remains majority-beaten (by D), and so now everyone is majority-beaten, and
>> A wins if s/he's the most top-rated.
>>
>> I haven't looked at what it would take for A to win in wv, because I no
>> longer propose wv for official public political elections (or any where
>> offensive strategy is likely). That would be something for a wv advocate to
>> discuss.
>>
>> Maybe I should list, together, some relative advantages of Bucklin &
>> MDDTR:
>>
>> Bucklin:
>>
>> * Easier protection of the CWs (relevant if one of your inbetween might
>> be the CWs)
>>
>> * Use-precedence
>>
>> MDDTR:
>>
>> * CD
>>
>> * LNHa
>>
>> * Precinct-Summability
>>
>> ----------------------------------------------------------------
>>
>> As for Bucklin's easier protection of the CWs, I'm not entirely sure,
>> because there's some reason for the individual to rank all of the best
>> candidates (instead of only ranking down to the CWse), to improve,
>> somewhat, the probabiliy of electing one of them (but not as much as
>> equal-top-ranking them all). So I don't know if Bucklin's easier protection
>> of the CWs would materialize..
>>
>> Michael Ossipoff
>>
>>
>>
>>
>>
>>
>>
>> Michael Ossipoff
>>
>>
>>
>>
>>
>> Maybe a toss-up. Bucklin has the use-precedence advantage, but MDDTR has
>> the precinct-summability adantage. And I consider MDDTR's LNHa an advantage
>> too, when you don't have to hesitate to append less-liked inbetweens to
>> your ranking for fear that you'll help the beat better candidaes.
>>
>> In Bucklin, when skipping is permitted, you could make sure that, above
>> some inbetween, you skip enough levels that the better candidates will have
>> enough rounds to accumulate the coalescing lower-choices that are coming to
>> them from other candidates' preferrers.
>>
>> In MDDTR, & maybe in Bucklin, I'd likely top-rate the CWse, along with
>> the very best of the strong top-set, even if s/he isn't really among those,
>> and even if I felt like down-rating some of that top-set a bit because of
>> some fault, or because of likely defection-inclination of their voters.
>>
>>
>>
>>
>>
>>
>> On Sat, Nov 12, 2016 at 2:56 PM, Forest Simmons <fsimmons at pcc.edu> wrote:
>>
>>> Perhaps we could modify (non-symmetric) ICT in order to have a less
>>> wordy definition of "strongly beat."
>>>
>>> Candidate X *strongly beats* candidate Y iff  X is preferred over Y on
>>> more ballots than Y is* ranked* equal to or above X.
>>>
>>> All strongly beaten candidates are disqualified unless that would
>>> disqualify all of them.
>>>
>>> Elect the qualified candidate ranked top on the most ballots.
>>>
>>> This definition makes it slightly harder for X to strongly beat Y than
>>> in standard ICT, because all equal rankings have to be overcome, not only
>>> those at the top.
>>>
>>> But it changes nothing in our standard CD examples, because in those
>>> examples there are no equal rankings (only equal truncations, which don't
>>> contribute to the strongly beat definition).
>>>
>>> It should preserve the FBC and perhaps even introduce a stronger
>>> property: if some candidate X is raised to the level of the winner on some
>>> ballots, then the winner is unchanged unless the new winner is X.
>>>
>>> I see the wisdom in saying "disqualified" instead of "eliminated."  If
>>> we said "eliminated," then some people would wrongly think that "favorite"
>>> refers to the highest among the remaining candidates (after their original
>>> favorite was stricken from the ballot).
>>>
>>> Also a comment about three slot methods in general:
>>>
>>> With three slots it is impossible for every candidate to be eliminated
>>> by a two-thirds majority.  So the following method would be even simpler to
>>> define in the context of 3 slot ballots:
>>>
>>> Elect the favorite candidate who is not beaten by a two-thirds majority.
>>>
>>> Of course, for all practical purposes that would be the same as "elect
>>> the candidate ranked top on the greatest number of ballots," which doesn't
>>> satisfy the CD criterion.
>>>
>>>
>>> On Sat, Nov 12, 2016 at 9:07 AM, Michael Ossipoff <
>>> email9648742 at gmail.com> wrote:
>>>
>>>> Yes, but ICT defines "beat" in a wordier way, that people hear as
>>>> complicated.
>>>>
>>>> For people who are into voting-systems, I can say "majority-beaten", &
>>>> they know what I mean...that I'm talking about pairwise defeats.
>>>>
>>>> So, here's how I'd define 3-Slot MDDTR, to the public:
>>>>
>>>> You rate each candidate as  "Top", "Middle", or "Bottom". If you don't
>>>> rate someone, that counts as rating hir at Bottom.
>>>>
>>>> The winner is the most    favorite candidate who doesn't have anyone
>>>> rated over hir by a majority.
>>>>
>>>> (If everyone has someone rated over hir by a majority, then the winner
>>>> is the most favorite candidate.)
>>>>
>>>> (end of definition)
>>>>
>>>> I'd just call it " Majority Disqualification".
>>>>
>>>> Michael Ossipoff
>>>> On Nov 11, 2016 4:39 PM, "Forest Simmons" <fsimmons at pcc.edu> wrote:
>>>>
>>>>> You wrote in part ...
>>>>>
>>>>> >Another advantage that it has over 3-Slot ICT is that 3-Slot MDDTR
>>>>> has a much >simpler definition:
>>>>>
>>>>> >The winner is the most favorite candidate who isn't majority-beaten.
>>>>>
>>>>> Three slot ICT could be defined in the same way;
>>>>>
>>>>> Elect the most favorite candidate who isn't strongly beaten.
>>>>>
>>>>> Neither definition tells what to do when every candidate is beaten
>>>>> (majority beaten or strongly beaten, respectively).  But that is just a
>>>>> detail of the definition that doesn't have to be mentioned immediately.
>>>>>
>>>>> Here's a more complete definition that works in both cases:
>>>>>
>>>>> Eliminate all candidates that are {majority, strongly} beaten unless
>>>>> that would eliminate all candidates.  Elect the most favorite among the
>>>>> remaining.
>>>>>
>>>>> So ordinary ICT and MDDTR are equally easy to define.  It's a matter
>>>>> of which has the best properties.
>>>>>
>>>>
>>>
>>
>
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